Signal device



08L 1940- H. F. OBERGFELL 2,217,073

SIGNAL DEVICE Filed Jan. 20, 1938 INVENTOR. HERBERT F. OBERGFELL W %MM ATTORNEYS Patented Oct. 8, 1940 UNITED STATES SIGNAL DEVICE Herbert F. Obergfell, River Forest, 111., assignor to Associated Electric Laboratories, Inc., Chicago, 111., a corporation of Delaware.

Application January 20, 1938, Serial No. 185,848

1 Claim.

The present invention relates to signal devices, and more particularly to ringers for use in telephone desk stands of the cradle type, or the like.

5 It is an object of the present invention to provide an improved signal device of compact and rugged construction which may be readily mounted directly within a telephone desk stand of the cradle type.

10 Another object of the present invention is to provide a signal device embodying an improved gong arrangement which occupies a minimum amount of space and which produces a pleasing tone.

5 In brief, the objects set forth above are in part realized in accordance with the present invention by providing in a signal device a pair of gongs arranged in nested relation in order to conserve space and secured to a support by an improved arrangement which accommodates adjustments of the positions of the gongs individually with respect to an associated gong striker. The gong striker is carried by a pivotally mounted armature and is adapted to en- 35 gage the gongs alternately. The gong striker is actuated into alternate engagements with the gongs by an arrangement including a magnetic core structure with which the pivotally mounted armature is associated.

so Further objects and advantages of the present invention will become apparent as the following description proceeds, and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

For a better understanding of the present invention, reference may be had to the accompanying drawing, in which Fig. 1 is a front elevational view of a ringer embodying the present inven- 40 tion; Fig. 2 is a side elevational view of the ringer shown in Fig. 1; Fig. 3 is an enlarged fragmentary side elevational view, partly in section, of the ringer taken along the line 33 of Fig. 1; and Fig. 4 is an exploded view, partly in section, of

the mounting arrangement for the gong striker shown in Fig. 3.

Referring now more particularly to Figs. 1, 2, and 3 of the drawing, there is shown a signal device or ringer comprising a magnetic core struc- 5 ture I0, 9. pivotally mounted armature H associated with the core structure l0, and a pair of nested gongs i2 and I3 carried by a support I4. The magnetic core structure I!) includes a substantially L-shaped permanent bar magnet I arranged adjacent a collar I6, a core member I"! extending through the collar lfi, and a pair of pole pieces l8 and- I9 carried by theopposite ends of the core member IT. The collar I6 is arranged intermediate the ends of the core member I! and is supported on a tubular sleeve lla thereon. 5 In order to prevent the setting up of eddy currents in the collar [6 due to variations in the magnetic flux passing through the core member I! during the operation of the ringer, the collar i6 is slotted along its lengthas indicated at I601. 10' The slot 16a interrupts the circuit of these eddy' currents in the'collar l6 about the core member I! which prevents these eddy currents from flowing in the collar l6. Insulating washers 20 and 2| encircling the core member I! are arranged on opposite sides of the collar l6, and insulating washers 22 and 23 encircling the core member I! are arranged adjacentth'e' pole pieces I8 and I9, respectively, in order to position a pair of magnetizing windings, shown dotted, carried by the core member l'l. One of the windings is adapted to surround the core member I! between the insulating washers 20 and 22, and the other of the windings is adapted to surround the core member I! between the insulating washers'2l 5 and 23. These magnetizing windings are soarranged that they produce accumulative magnetic fluxes in the core member-"l Lwhen they are connected in series across a'suitable source o-f'alternating current supply. l

As best shown in Figs. 3 and 4, the armature supporting arrangement comprises a substantiall U-shaped bracket 24 secured to the lower portion of the collar I6 and having a pair of spaced apart arms 25 and 26. opening 28 is 35. formed in the arm 25 adjacent the outer end thereof, and a somewhat larger opening 29' is formed in the arm 26 adjacent'the outer end thereof, these openings being'arranged in alignment with each other in order to receive a pin member 30 extending between the arms 25 and 26. One end of the pin member 30 is provided with a knurled portion 3|, which is adapted fric tionally to engage the inner surface of the open-'-' ing 28 formed in the arm 25 in order to retain 4'5 this end of the pin member 30 firmly in place. The opposite end of the pin member 30 extends" through the opening 29 formed in the arm 26, and is arranged in spaced relation to the surrounding inner surface of this opening. The: inner surface of the opening 29 formed in the arm 26 is threaded to receive an externally threaded hollow bushing 32, which fills the intervening space between the inner surface of' the opening 29 and the end of the pin member 30' extending through the opening 29, this end of the pin member 30 being snugly accommodated in the opening formed in the hollow bushing 32. By forming the opening in the bushing 32 closely to conform to the exterior surface of the free end of the pin member 30, the hollow bushing 32 may be made closely to surround the free end of the pin member 30 which extends through the opening-29 formed in the arm 26 and firmly to retain this end of the pin member 30 in place. The hollow bushing 32 is provided with an enlarged head which is slotted as indicated at 33,

in order to receive a screw driver or the like to facilitate placement and removal of the hollow bushing 32. A threaded locknut 34 is arranged on the threaded portion of the hollow bushing 32 in order to retain the hollow bushing 32 secur'ely in place on the arm 26 of the bracket 24, The armature supporting arrangement also includes a substantially U-shaped bracket 35 providedwith a pair of spaced apart arms 36 and 31 having aligned openings 33 and 39, respectively, formed therein, which serve as bearings for pivotally supporting the bracket 35 on the pin member,30, the bracket 35 being retained in position on the pin member 30 by the inner end of the hollow bushing 32. The armature II is secured intermediate its ends to the bracket 35 by a pair of rivets 40. Inorder to prevent the ends of the armature II from sticking to the faces of the pole pieces I8 and I9 during the operation of the ringer, a shim 4I formed of non-magnetic material 'is clamped between the armature II and the bracket 35 and extends between the ends of the armature I I and the faces of the pole pieces I8 and IS. The armature II is provided with an offset arm 42 which carries a striker 43 having a striking head 44 arranged between the gongs I2 and I3, and adapted to engage the gongs alternately. The end of the armature II arranged adjacent the pole piece I8 is biased toward the pole piece I8 by an arrangement including a spring 45 extending between the offset arm 42 provided on the armature II and a clip 46 securedto the support I4 by a screw 41, the screw 4'! also serving to secure the support I4, the collar I6,- the tubular sleeve- I'Ia, the core member I1, and the bracket 24 in assembled relation.

- As best shown in Fig. 3, the permanent bar magnet I5 is secured to the bracket 24 by an arrangement including a clip 48, the clip 48 being fastened to an enlarged portion of the arm 25 of the bracket-24 by a pair of screws 49. The collar I6, the core member II, the pole pieces I8 and I9, and the armature II are all formed of magnetic material. One end of the permanent bar magnet I5 is arranged in contact with the collar I6, and the other end of the permanent bar magnet I5 is arranged in spaced relation and closely adjacent the armature II. When the magnetizing windings carried by the core memher I! are not energized, the permanent bar magnet I5 establishes a. magnetic field through the core structure I0 and the associated armature I I, which imparts to the respective ends of the armature II a predetermined polarity influence and to the pole pieces I8 and I9 the opposite polarity influence. The forces produced by these polarity influences tend to move the ends of the armature II toward the pole pieces I8 and I9. However, the end of the armature II arranged adjacent the pole piece I8 is biased toward the pole. piece I 8 by the biasing spring 45.

During the operation of the device and when the magnetizing windings surrounding the core member I! are energized from a suitable source of alternating current supply, an alternating magnetic field is set up through the core structure I0 and the associated armature II which, together with the magnetic field established by the permanent bar magnet I5 through the core structure I0 and the associated armature II, causes the armature I I to oscillate. about its pivot provided by the pin member 30. The end of the armature II arranged adjacent the pole piece I9 against the bias of the spring 45 is moved toward the pole face of the pole piece during one-half of each cycle of the applied voltage, and the end of the armature II arranged adjacent the pole piece I8 is moved toward the pole face of this latter pole piece during the other half of each cycle of the applied voltage. Thus the ringer is of the polarized type, and the striking head 44 of the striker 43 is actuated into alternate striking engagements with the gongs I2 and I 3.

In order to providev a distinctive composite tone, the gongs I2 and I3 are so constructed and arranged that they have different natural frequencies of vibration and individually produce different tones when they are struck by the striking head 44 of the striker 43. Thus the ringer is of the dual tone type and produces two distinct tones when it is operated, these tones blending to produce a particularly pleasing audible sound. Each of the gongs I2 and I3 is of substantially cup-shaped configuration and comprises an end wall provided with an opening therethrough which is eccentrically located with respect to the geometric center thereof. In Fig. 1, the centers of the openings provided'through the gongs I2 and I3 are indicated at 50, the geometric center of the gong I2 is indicated at 5|, and the geometric center of the gong I3 is indicated at 52. The gong I2 is secured to the support I4 by an arrangement including a threaded member 53 extending through the eccentrically located opening provided in the gong I 2, the member 53 being arranged in threaded engagement with an internally threaded opening formed in the support I4 adjacent the upper end thereof. The threaded member 53 is provided with an enlarged hollow head 54 which is internally threaded to receive a threaded member 55 extending through the eccentrically located opening provided in the gong I3. Thus the threaded members 53 and 55 provide a common arrangement for securing the gongs I2 and I3 to the support I4 and in spacedapart, relationship with respect to each other, the gong I2 being directly secured to the support I4 by the threaded member 53, and the gong I3 being directly secured to the enlarged head 54 of the threaded member 53. This common arrangement also accommodates adjustments of the positions of the gongs I2 and.I3 individually with respect to the striking head 44 of the striker 43.

In order to adjust the position of the gong I2 with respect to the striking head 44 of the striker 43, the threaded member 53 is loosened and the gong I2 is rotated about the threaded member 53. Due to the eccentric location of the opening provided in the gong I2 with respect to its geometric center 5I this rotation causes the struck surface of the gong I2 to be moved toward or away from the striking head 44 of the striker 43. After the gong I2 has been rotated to the desired adjusted position, the threaded member 53 is. tightened to retain the gong I2 securely in place. In order to adjust the position of the gong I3 with respect to the striking head 44 of the striker 43, the threaded member 55 is loosened and the gong I3 is rotated about the threaded member 55. Here again, the eccentric location of the opening provided in the gong l3 with respect to its geometric center 52 causes the struck surface of the gong l3 to be moved toward or away from the striking head 44 of the striker 43. After the gong l3 has been rotated to the desired adjusted position, the threaded member 55 is tightened to retain the gong l3 securely in place.

From the foregoing description it is apparent that a signal device or ringer is provided which is of rugged construction and comprises a minimum number of parts. Moreover, the ringer occupies a minimum amount of space, due to the nested relation of the gongs embodied therein, which permits the ringer to be mounted directly within a telephone desk stand of the cradle type.

While a particular embodiment of the present invention has been shown, it is not desired that the invention be limited to the particular construction shown and described, and it is intended in the appended claim to cover all modifications within the spirit and scope of the present invention.

I claim:

A signal device comprising inner and outer gongs arranged in spaced-apart and nested relationship, each of said gongs being substantially cup-shaped and having an end wall provided with an eccentrically located opening therein, a support arranged exteriorly of said outer gong and adjacent the end wall thereof, means including a first member extending through the opening in the end wall of said outer gong and threaded into an opening provided in said support for securing the end wall of said outer gong to said support, means including a second member extending through the opening in the end wall of said inner gong and threaded into an opening provided in said first member for securing the end wall of said inner gong to said first member, means including a head carried by said first member and disposed between the end walls of,

said gongs for retaining said gongs in spacedapart nested relationship, a striker having a striking head arranged between said gongs in striking relationship therewith, said outer gong being rotatable about said first member to accommodate adjustment of the position thereof with respect to the striking head of said striker, said inner gong being rotatable about said second member to accommodate adjustment of the position thereof with respect to the striking head of said striker, and means for actuating the striking head of said striker into alternate striking engagements with said gongs.

HERBERT F. OBERGFELL. 

